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Biomedical subjects

M Monden

Publications and source records attributed to M Monden.

At least 487 records · Page 27Linked to original sources
PubMedDate not supplied

Intrahepatic cholangiocarcinoma with marked hypervascularity.

Two rare cases of small intrahepatic cholangiocarcinoma with marked hypervascularity are reported. Dynamic computed tomographic and magnetic resonance images of the two cases revealed strong enhancement of the whole tumor on the early phase and prolonged enhancement on the late and delayed phases. In both cases, the tumors turned out to be well-differentiated tubular cholangiocarcinoma that contained a large number of tumor cells and few interstitial fibrous tissues. These results suggest that some intrahepatic cholangiocarcinoma should be differentiated from other hypervascular hepatic tumors, especially hepatocellular carcinoma, and that prolonged enhancement of the tumor on late and delayed phases of dynamic images could be of diagnostic value.

Bile Duct Neoplasms↗
PubMedDate not supplied

Prolongation of cardiac allograft survival by intraportal injection of donor antigens--differential mechanisms according to the timing of injection.

Recently, we reported that intraportal (IP) injection of donor spleen cells (SPCs) before transplantation as well as at the time of transplantation significantly prolongs cardiac allograft survival in rats (7). Long-term establishment of chimerism induced by intraportal administration of SPCs could be a part of this prolongation. In this study, we examined the effect of irradiation of SPCs as a source of donor antigens on cardiac allograft survival. Experiments were carried out using DA (RT1a) as the donor and BUF (RT1b) as the recipient strain. Fifty million irradiated or nonirradiated SPCs were injected either intravenously (i.v.) or intraportally (i.p.) on day -10 or day 0, the day of cardiac allografting. Untreated animals rejected allografts within a mean survival time (MST) of 7.2 +/- 0.8 days (n = 5). Injection (i.p.) of SPCs on both day -10 (n = 4) and day 0 (n = 6) induced significant prolongation of MST over the control (19.0 +/- 4.7, 14.2 +/- 2.1 days; p < 0.001 vs. control), while i.v. injection of SPCs on either day -10 (n = 4) or day 0 (n = 4) failed to do so (9.2 +/- 1.0, 8.5 +/- 0.6 days). Significant prolongation was still observed when irradiated SPCs were injected on day -10 (n = 4; MST: 19.0 +/- 5.4 days, p < 0.002 vs. control), but not when injected on day 0 (n = 5; MST: 9.4 +/- 2.1 days). These data suggest that the immunosuppressive effect of i.p. injection of donor SPCs could be induced by differential mechanisms according to the timing of inoculation of donor antigens.

Animals↗
PubMedDate not supplied

Siderotic nodules in hepatic cirrhosis disappearing after biliary hemorrhage: MR imaging.

Magnetic resonance demonstrated siderotic regenerating nodules in a patient with hepatocellular carcinoma with accompanying liver cirrhosis. The siderosis disappeared when iron deficiency anemia developed in association with biliary hemorrhage. Magnetic resonance was sensitive enough to follow changes in the siderosis. The mechanism of iron deposition in regenerating nodules that accompanied liver cirrhosis did not seem to be related to the severity of the liver damage.

Anemia, Hypochromic↗
PubMedDate not supplied

CT and MRI of siderotic regenerating nodules in hepatic cirrhosis.

The demonstration by CT of siderotic regenerating liver nodules in cirrhosis was evaluated and compared with that of MR imaging retrospectively in 27 patients with histologically diagnosed hepatic cirrhosis. Only in one of the two patients with marked iron deposits in regenerating nodules did CT demonstrate multiple high density nodules. In the other patient with marked iron deposits and in seven of the nine patients with moderate iron deposits, the liver parenchyma on CT was demonstrated as heterogeneous and of slightly high density without focal nodules. In 8 patients with mild to moderate iron deposits and in the 10 with no iron deposits, the liver parenchyma was homogeneous on CT. Multiple low intensity nodules in the liver were seen on fast low-angle shot (FLASH) MR images in all 17 patients with iron deposits in regenerating nodules. No low intensity nodules were seen on FLASH MR images in the 10 patients with no iron deposits. If there are iron deposits above a certain level, siderotic regenerating nodules may appear as nodules of high density on CT or as heterogeneous regions of high density liver parenchyma. Magnetic resonance is more sensitive than CT in demonstrating siderotic regenerating nodules.

Adult↗
PubMedDate not supplied

Expression of p16 and cyclin-dependent kinase 4 proteins in primary breast carcinomas.

The immunolocalization of the p16 and cdk4 proteins was investigated in 65 retinoblastoma gene product (pRB)-positive and 20 pRB-negative breast carcinomas. These proteins were expressed in similar lesions in 84.6% of the pRB-positive and 100% of the pRB-negative carcinomas. Diffuse expression of p16 was observed in 73.8 and 70.0% of the pRB-positive and -negative cases, respectively. cdk4 and p16 expression was significantly more heterogeneous in tumors of larger sizes and/or at higher stages. These findings suggest that p16 can be induced regardless of pRB status and Rb gene function in primary breast carcinoma and that it modulates the cell cycle progression in association with cdk4.

Blotting, Western↗
PubMedDate not supplied

Effects of nucleosides and a nucleotide mixture on gut mucosal barrier function on parenteral nutrition in rats.

BACKGROUND: We have previously reported that the addition of nucleosides and a nucleotide mixture (OG-VI) to total parenteral nutrition (TPN) prevents TPN-induced intestinal mucosal atrophy and results in increased intestinal cathepsin activities under TPN. The aims of the present study are to examine the effects of OG-VI on mucosal barrier functions and to clarify whether the intestinal cathepsins can be used as a new marker of mucosal barrier function. METHODS: Male Wistar rats were divided into three groups: FED (food ad libitum), TPN (a standard TPN solution), and OG (OG-VI in addition to the TPN solution). Mucosal barrier functions were analyzed by the lactulose/mannitol (L/M) test, mucosal ZO-1 messenger RNA level, and electron micrographs in the gut. Intestinal cathepsin B, H, and L activities were also measured. RESULTS: The L/M ratio for TPN was much higher than that for FED. Only lactulose excretion was significantly reduced by OG-VI. The intercellular spaces of the mucosal cells for TPN were significantly wider than those for FED, but were reduced in size by the addition of OG-VI. All cathepsin activities of the ileum were higher for TPN than for FED, whereas OG showed no increase. CONCLUSION: OG-VI contributes to the improvement of gut mucosal barrier function. Intestinal cathepsin activities can be used as a new marker of mucosal barrier function.

Animals↗
PubMedDate not supplied

Nucleotides and intestine.

BACKGROUND: Dietary nucleotides play an important role in the growth and development of the intestine. Parenteral supplementation of nucleic acids may be necessary to maintain the mucosal proliferation and barrier functions during parenteral nutrition (PN). METHODS: Male Wistar rats were divided into 3 groups: FED (food ad libitum with saline infusion); PN (a standard PN solution); and OG (OG-6, a mixture of nucleotide and nucleosides, in addition to the PN solution). The mucosal wet weight, protein, and DNA contents, villous height and crypt depth, electronmicroscopic examination of the intercellular junctions, proliferating activity of the mucosal cells, mucosal permeability, bacterial translocation, and mucosal cathepsin activities were examined. RESULTS: The wet weight, protein, and DNA contents of the jejunal mucosa were significantly increased in the OG group, compared with those in the PN group. The morphometric examination revealed a significant increase in the villous height but not in the crypt depth in the OG group. The widths of both the tight and intermediate junctions were narrower in the OG group than those in the PN group. The activity of diamine oxidase was increased in the OG group, compared with that in the PN group. The ratio of proliferating cell nuclear antigen positive cells and the index of bromodeoxy uridine labeling index in the OG group were as high as in the FED group, and significantly higher than those in the PN group. The portal concentration of fluorescein isothiocyanate-dextran 70,000 after intragastric loading was significantly higher in the PN group than that in OG group. Likewise, the rate of urinary lactulose excretion after intragastric loading was higher in the PN group. The positive rate of bacteria cultured in mesenteric lymph nodes was higher in the PN group than in the OG group although the difference was not significant. The activities of mucosal cathepsins (B, H, and L), markers for phagocytic degradation of extrinsic substances and organisms, were higher in the PN group than those in the OG and FED groups. CONCLUSIONS: Parenteral supplementation of nucleic acids supports the mucosal cell proliferation and functions.

Administration, Oral↗
PubMedDate not supplied

Role of the liver in alloimmune response following inoculation of donor spleen cells.

The liver is thought to be an immunologically privileged organ in the response to inoculated antigens. We previously demonstrated that it is possible to localize inoculated antigens to the liver alone or only to extrahepatic tissue using orthotopic syngeneic liver transplantation (OSLT). In this study, we analyzed more detailed mechanisms of the anti-alloimmune response in the liver. DA rat spleen cells were systemically injected into WS rats (donor spleen cell inoculation, DSI). In the sensitized liver-grafted (SLG) group, after DSI, liver grafts were retrieved from sensitized WS rats, then transplanted into naive WS rats. In the sensitized liver-removed (SLR) group, after DSI, WS rats were totally hepatectomized and given livers transplanted from naive WS rats. All the rats were challenged with heterotopic heart grafts 10 days after DSI. Mean heart graft survival in the control, DSI, SLG, and SLR groups were 11.6+/-1.6, 10.7+/-2.4, 4.4+/-1.0, and 24.6+/-6.3 days, respectively. Accelerated rejection in the SLG group as well as graft prolongation in the SLR group disappeared when OSLT was performed 2 days after DSI or later. Irradiation of DA splenocytes before inoculation did not alter graft survival in SLG. However, pretreatment with gadolinium chloride prior to DSI attenuated the antidonor response in the SLG group. In conclusion, a vigorous antidonor response occurred in the liver after systemic inoculation of spleen cells. It peaked I day after DSI and disappeared rapidly. Kupffer cells seemed to play an important role in this phenomenon.

Animals↗